Respostas

2013-05-25T23:58:23-03:00

Δ = b2 - 4.a.c 
Δ = 162 - 4 . 4 . 15 
Δ = 256 - 4. 4 . 15 
Δ = 16

Há 2 raizes reais.

 

Aplicando Bhaskara:

x = (-b +- √Δ)/2a

 

x' = (-16 + √16)/2.4     x'' = (-16 - √16)/2.4 x' = -12 / 8     x'' = -20 / 8 x' = -1,5     x'' = -2,5
1 1 1
2013-05-26T00:40:55-03:00

Δ = b2 - 4.a.c 
Δ = 162 - 4 . 4 . 15 
Δ = 256 - 4. 4 . 15 
Δ = 16